JPH10186577A - Base for image material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the liquid adhesiveness at the beginning of coating when high- speed coating application is executed and to enable the sufficient adhesion between an image material base and an image forming layer by coating and providing the resin layer side on the side where the image forming layer is disposed with an under coating layer and maintaining the surface potential on the under coating layer surface at plus potential. SOLUTION: The resin layer (A) side provided with the image forming layer is coated and provided with the under coating layer and the surface potential of the under coating layer surface is the plus potential. More specifically, the image material substrate is preferably produced by subjecting the resin layer (A) side to a corona discharge treatment, then coating and providing the resin layer side with the under coating layer after applying the plus potential thereto. Further, the corona discharge treatment, the impartation of the plus potential and the coating application of the under coating layer are preferably executed in succession on-machine, i.e., by a tandem system. The execution of the corona discharge treatment with adequate intensity by an adequate device is recommended for the corona discharge treatment. The surface potential of the base before the coating application of the under coating layer is preferably plus >=30 volts. The surface potential of the under coating layer surface after coating application and drying is preferably plus >=5 volts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a paper substrate on which one image forming layer is provided (hereinafter referred to as "base paper"). A resin layer (A) containing a certain resin (a) is coated with a subbing layer on the side of the resin layer (A), and a paper substrate on the opposite side is a resin containing a resin (b) capable of forming a film. The present invention relates to a resin-coated paper-type image material support coated with a layer (B), and more particularly, to a coating liquid for an image forming layer, which has good wettability at the beginning of coating and is suitable for an image material. The present invention relates to an image material having sufficient adhesion to a film and capable of providing a sufficient adhesion between a support and an image forming layer, and a resin-coated paper type image material support capable of providing a print thereof.

[0002]

2. Description of the Related Art Usually, an image material is composed of a support for an image material and an image forming layer provided on the support. For example, a silver halide photographic material, an ink jet recording material, a heat transfer type thermal transfer recording image-receiving material, a heat-sensitive recording material, a light-sensitive heat-sensitive recording material, and the like are each provided on a support for an image material, a silver halide photographic component layer, an ink image-receiving layer, An image forming layer such as a heat transfer type thermal transfer recording image receiving layer, a thermosensitive coloring layer, a photosensitive thermosensitive coloring layer, and auxiliary functional layers such as an undercoat layer, a protective layer, and a backing layer are provided as needed. In particular, silver halide photographic constituent layers include a silver halide photographic emulsion layer,
Protective layer, undercoat layer, intermediate layer or anti-color mixing layer, anti-halation layer, or filter layer, ultraviolet absorbing layer,
It is composed of a back layer and the like and a combination thereof. For example, a single silver halide photographic material has a silver halide photographic emulsion layer and a protective layer provided on a photographic material support. Further, a multilayer silver halide color photographic material comprises an undercoat layer, a blue-sensitive silver halide photographic emulsion layer and an intermediate layer, a green-sensitive silver halide photographic emulsion layer and an ultraviolet absorbing layer, A silver halide photographic emulsion layer and a silver halide color photographic constituting layer such as a protective layer are provided in this order and are arranged in multiple layers.

Heretofore, resin-coated paper-type supports in which a base paper surface for an image material support is coated with a resin capable of forming a film are well known. As a support for a resin-coated paper type photographic material for silver halide photographic materials, for example, Japanese Patent Publication No. 55-12584 discloses that a base paper is coated with a film-forming resin, preferably a polyolefin resin. In addition, a technique for a support for a photographic material has been disclosed. U.S. Pat. No. 3,501,298 discloses a technique for a photographic material support in which both sides of a base paper are coated with a polyolefin resin. Further, since the rapid photographic development processing method of silver halide photographic materials was applied, supports for photographic materials in which both sides of a base paper were coated with a polyethylene resin have been mainly put to practical use for photographic printing paper. If necessary, the resin layer on the side on which one of the image forming layers is provided usually contains a titanium dioxide pigment for imparting sharpness.

Further, US Pat. No. 4,774,224 discloses that
There has been proposed a thermal transfer recording image receiving element having as a support a resin-coated paper having a resin coating having a surface roughness of 7.5 microinch-AA or less, particularly a polyethylene resin-coated paper in which the surface of a base paper is coated with a polyethylene resin. . In addition,
JP-A-63-307979 discloses a technique relating to an ink jet recording sheet having a resin-coated paper as a support.

However, a resin-coated paper-type image material support in which the surface on which the image forming layer is provided of a base paper, especially a base paper mainly composed of natural pulp, is coated with a resin layer still has some serious problems. In fact, there are still many problems and satisfactory results have not yet been obtained.

First, the side on which the image forming layer of a base paper mainly composed of natural pulp is provided (hereinafter, the side on which the image forming layer is provided is the front side, the resin layer coated on the front side is the front resin layer, and the opposite side is the opposite side). On the back side, the resin layer coated on the back side may be abbreviated as the back resin layer) with a resin layer containing at least a film-forming resin, and the back side of the base paper with a resin layer containing a film-forming resin. When producing an image material using a coated resin-coated paper as a support, there is a problem regarding the applicability of a coating solution for an image forming layer. That is, when applying the image forming layer coating solution to the image material support, when the image forming layer coating solution is applied to the image material support from the coating head, hardly applied from the application start point, Alternatively, there is a problem in that the liquid is not uniformly applied, but is formed in a saw-tooth shape and is thickly applied. It is out of the question that the coating solution for the image forming layer is not applied, and a saw-toothed coated product does not become a product at all, and a thick coating does not become a product. There was a problem of causing the above troubles.

[0007] When the coating solution for the image forming layer is applied to the support for the image material, the wettability at the beginning of coating (hereinafter, may be simply abbreviated as the wettability) becomes higher as the coating speed increases. In addition, there is a problem that the liquid sticking property is further deteriorated. The inventors of the present invention have studied the coating property of the image forming layer coating liquid on the resin-coated paper type image material support, and found that the coating speed was 150 m in the slide hopper method or the extrusion bar method. / Min or more,
In particular, it was found that the liquid adhesion was particularly poor at 200 m / min or more. In addition, it was found that in the curtain coater method of 250 m / min or more, the liquid adhesion was significantly deteriorated. Furthermore, in the multilayer simultaneous coating method, it has been found that there is also a problem that the larger the number of layers to be coated, the worse the liquid adhesion becomes.

[0008] Secondly, the side of the base paper mainly composed of natural pulp on which the image forming layer is provided is coated with a resin capable of forming a film, especially a resin layer containing a polyolefin resin, and the back side of the base paper is capable of forming a film. Resin-coated paper coated with a resin layer containing a resin has a problem in that the adhesion between the support and the image forming layer of an image material using the resin-coated paper as a support is insufficient. In particular, in the case of photographic materials that require development processing with a developing solution, especially silver halide photographic materials, the resin-coated paper type support and the photographic constituent layers, particularly the wet and swollen state of the silver halide photographic constituent layers However, there was a problem that the adhesiveness and the provided emulsion film were poor. A silver halide photographic material having a poor emulsion film coating is such that the silver halide photographic constituent layer is completely or partially peeled from the support during the development processing,
There has been a problem that the film surface is scratched, and the film surface has no practical value.

Several proposals have been made to improve the coating properties of a coating solution for a photographic constituent layer of a support for a resin-coated paper type photographic material. The simplest method for improving the coating properties of a resin-coated paper-type support for a photographic material and providing good adhesion between the support and the photographic component layer is disclosed in British Patent Nos. 971,058 and 1,060,526. As described in the publications, it means that the resin surface of the resin-coated paper type photographic material support is subjected to electron impact. Electron impact is also known as corona discharge treatment. However, even when a surface of a resin-coated paper type photographic material support is subjected to corona discharge treatment, it is extremely insufficient to improve the liquid repellency of the coating solution when the coating solution for a photographic constituent layer is applied at a high speed. However, in some cases, significant coating unevenness, which is considered to be caused by corona discharge unevenness, occurred.

Japanese Patent Application Laid-Open No. 62-260149 proposes to provide an undercoat layer containing gelatin on the surface of a support for a resin-coated paper type photographic material. JP-A-1-137252 proposes to provide a gelatin subbing layer having an instantaneous water wettability of 53 dyn / cm or more. However, even when the undercoat layer is provided, it is extremely insufficient to improve the liquid adhesion of the photographic composition layer when the photographic composition layer coating solution is applied at a high speed.

Further, JP-A-63-4881 discloses a method of applying a coating solution by applying an electrostatic field to a support provided with a gelatin subbing layer containing a surfactant and then applying a coating solution. Although techniques for improving the properties have been proposed, the use of such techniques has not yet provided sufficient liquid repellency of the coating solution for the image forming layer.

As described above, the surface of the base paper, especially the base paper mainly composed of natural pulp, on which the image forming layer is provided, is coated with a resin layer containing a film-forming resin, particularly a polyolefin resin. Little is known about the liquid-appearing property at the beginning of coating of a resin-coated paper-type image material support in which the back side of the resin is coated with a resin layer containing a resin capable of forming a film, and the image is formed using a conventionally known technique. When a coating solution for forming layer is applied at a high speed, liquid adhesion is very good, and adhesion between the support and the image forming layer, particularly, a resin-coated paper type image material support having good emulsion film adhesion. I couldn't get my body.

[0013]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to use a paper mainly composed of natural pulp as a substrate, and the paper substrate on which one of the image forming layers is provided is a resin (a) capable of forming a film. A resin substrate coated with a resin layer (A), and a paper substrate on the opposite side coated with a resin layer (B) containing a film-forming resin (b). , When the coating solution for the image forming layer is applied at a high speed, the coating property at the beginning of coating is extremely good, and sufficient adhesion between the support for the image material and the image forming layer can be obtained. It is an object of the present invention to provide an image material having good adhesion of a silver photographic constituent layer in a wet and swollen state and having a desired emulsion film, and a resin-coated paper type image material support capable of providing a print thereof. Other objects of the present invention will become clear from the description of the following specification.

[0014]

The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, the paper on which one of the image forming layers is to be provided, using a paper mainly composed of natural pulp as a substrate. An image material support in which a paper substrate is coated with a resin layer (A) containing a film-forming resin (a) and an opposite paper substrate is coated with a resin layer (B) containing a film-forming resin. Wherein the undercoat layer is coated on the resin layer (A) side on which the image forming layer is provided, and the surface potential of the undercoat layer surface is a positive potential, As a result, it has been found that the object of the present invention is achieved.

Here, the surface potential can be measured by a commercially available surface potential measuring device comprising at least a probe and a surface voltmeter. The surface potential referred to in the present invention refers to the average surface potential. As the surface potential measuring device, a high-precision device equipped with a measuring distance compensation function and the like is preferable. For example, S2001, a high-precision surface potential measuring device manufactured by Kawaguchi Electric Works Co., Ltd. can be mentioned.

The object of the present invention is achieved effectively by subjecting the resin layer (A) side to a corona discharge treatment, thereafter applying a positive potential, and then applying an undercoat layer. Has been found to be remarkably achieved by making the surface potential of the positive electrode of preferably +5 volts or more, more preferably +10 volts or more, and particularly preferably +20 volts or more. The object of the present invention is
It has been found that this can be achieved significantly by incorporating gelatin, preferably low molecular weight gelatin, in the undercoat layer. Further, an object of the present invention is to contain an inorganic compound containing an anionic surfactant or Cr (III) ion or Al (III) ion in addition to gelatin in the undercoat layer, and preferably contain them in combination. As a result, the present invention has been found to be more remarkably achieved, and has led to the present invention.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The support for an image material according to the present invention has an undercoat layer coated on the resin layer (A) side on which the image forming layer is provided, and the surface potential of the undercoat layer surface is positive. Of electric potential. Specifically, the support for an image material in the present invention is produced by applying a corona discharge treatment to the resin layer (A) side, applying a positive potential, and then applying an undercoat layer to the resin layer side. Are preferred. More specifically, in the present invention, an embodiment in which the corona discharge treatment, the application of the positive potential, and the application of the undercoat layer are successively performed on-machine and performed in a contract tandem system is particularly preferable.

As the corona discharge treatment, it is preferable to carry out a corona discharge treatment with an appropriate strength by using an appropriate corona discharge treatment device. Specific methods of corona discharge treatment include the type of corona output machine, the type and shape of corona bar,
Corona treatment conditions such as frequency, anodic current, air gap, type and properties of the resin layer (A) of the image material support, and traveling speed of the image material support can be experimentally set in advance.

In the present invention, it is preferable to apply a positive potential to the surface resin layer (A) side of the image material support after the corona discharge treatment and before the application of the undercoat layer. For applying the positive potential, the surface potential of the support before coating the undercoat layer is preferably at least 30 volts, more preferably at least 400 volts, particularly preferably at least 50 volts.
Set to 0 volts. Thus, the surface potential of the surface of the undercoat layer after application and drying of the undercoat layer as described herein can be preferably at least 5 volts, more preferably at least 10 volts, and particularly preferably at least 20 volts. . As a specific method of applying a positive potential before applying the undercoat layer, it is possible to apply a high voltage to a DC electrode that is in contact with or non-contact with the image material support after corona discharge treatment. I can do it. Specifically, a method in which a DC high voltage is applied to the wire-like conductive material facing in a non-contact manner over the width direction of the image material support to apply electricity to the support, the width direction of the image material support A system in which a DC high voltage is applied to the bar-shaped conductive material facing in a non-contact manner over the non-contact type to apply power to the support, a roll contacting in the width direction of the image material support, preferably a backup roll, particularly Preferably, it can be carried out by a method of applying a high DC voltage to the application backup roll to apply electric power to the support, or a combination thereof. Specific examples of the roll charging method can be performed by the methods described in JP-A-61-146369 and JP-A-63-4881.

In the present invention, various gelatins preferably used for the undercoat layer include lime-treated gelatin, acid-treated gelatin, enzyme-treated gelatin, and gelatin derivatives, for example, gelatin reacted with dibasic acid anhydride. Can be mentioned. In addition, other hydrophilic polymers such as polyvinyl alcohol and starch can be used in combination with gelatin. Further, the pH of the undercoating liquid is not particularly limited, but from the viewpoint of the storability of the photographic material, the pH is
H8 or less is preferable, and pH 7 or less is more preferable.

From the viewpoint of remarkably improving the liquid adhering property of the coating solution for the image forming layer according to the present invention, it is preferable to use a low molecular weight gelatin as the gelatin contained in the undercoat layer. The amount of low molecular weight gelatin used is preferably 20% by weight or more based on the total amount of gelatin in the undercoat layer. As used herein, low molecular weight gelatin is defined as having a molecular weight of 7
10,000 or less, preferably 500 to 60,000, and particularly preferably 1 to
000 to 40,000, and preferably a viscosity of 1 centipoise (hereinafter simply abbreviated as cp) to 2 cp as determined by the PAGI method. Further, as a method for producing low molecular weight gelatin, for example, it can be produced by the method described in JP-A-4-60633.

The coating amount of the undercoat layer is not particularly limited, but the coating amount of gelatin is 0.1% by weight to 10% by weight.
Wt% of water-based coating solution well is to apply ^{1g / m 2 ~40g / m 2} , from the viewpoint of adhesiveness improving effect of a liquid with properties of the image forming layer coating solution and the support and the image forming layer, 0.0 by solid weight
05g / m ² ~2.0g / m ² range is preferred, 0.01g / m ² ~
The range of 1.0 g / m ² is more preferable, and 0.02 g / m ^{2 to} 0.1 g / m ² .
A range of 5 g / m ² is particularly preferred.

In addition to gelatin, an anionic surfactant or Cr (II) may be added to the undercoat layer in the undercoat layer in order to remarkably improve the liquid adherability of the coating solution for the image forming layer according to the present invention.
It is preferable to include an inorganic compound containing I) ion or Al (III) ion, and it is particularly preferable to use them in combination. Examples of the anionic surfactant preferably used in the present invention include polyoxyethylene alkylphenyl ether sulfate, polyoxyethylene alkyl ether sulfate, alkylbenzene sulfonate, sulfosuccinate, and the like. Sulfosuccinic acid ester salts are particularly preferred from the viewpoint of a synergistic effect of improving the properties, and specific examples thereof include sodium 2-ethylhexylsulfosuccinate. The coating amount in the undercoat layer of the anionic surface active agent, the effect of the present invention, in particular in terms of the effect of improving the liquid with properties, the range of 0.1mg / m ² ~3mg / m ² are preferred, more preferably in the range of ^{0.3mg / m 2 ~2.5mg / m 2} , the range of 0.6mg / m ² ~1.5mg / m ² is particularly preferred.

The Cr (I) preferably used in the present invention
Examples of the inorganic compound containing the II) ion or the Al (III) ion include chrome alum, chromium sulfate, potassium alum, and the like. Particularly preferred. The coating amount of the inorganic compound in the undercoat layer (coating amount as a hydrated salt) is preferably 0.4 mg / m.
The range of m ^{2 to} 10 mg / m ² is preferable, and 1.2 mg / m ^{2 to} 10 mg / m ²
more preferably m ² range, the range of 2 mg / m ² to 10 mg / m ² is particularly preferred.

Further, various additives can be contained in the undercoat layer. As a preservative, p-hydroxybenzoic acid ester compounds described in or exemplified in JP-A-1-102551, benzisothiazolone compounds, isothiazolone compounds, etc., as surfactants, in addition to anionic surfactants, saponins, alkylene oxides Nonionic surfactants, such as JP-B-47-9303, U.S. Pat.
Fluorinated surfactants described in 3,589,906, etc., sulfobetaine-based amphoteric surfactants, amino acids, amphoteric surfactants such as esters of amino alcohols, hardening agents, active halogen compounds, vinyl sulfone compounds,
Hardening agents such as aziridine compounds, epoxy compounds, acryloyl compounds, and isocyanate compounds, as well as toning agents, optical brighteners, matting agents, fog inhibitors or stabilizers, p
An H regulator and the like can be appropriately combined and contained.

As a method of providing the undercoat layer on the surface resin layer (A) side, the resin layer (A) on the side on which the image forming layer is provided before coating the resin layer on the running base paper surface and before winding. It is preferable to carry out a so-called on-machine method, in which an undercoat coating solution is applied and dried on the side to provide an undercoat layer. Further, after winding the resin-coated paper, if necessary, after storing the winding, a subbing layer may be newly provided, that is, a so-called off-machine method. Examples of an apparatus for applying the undercoating liquid include an air knife coater, a roll coater, a bar coater, a wire bar coater, a blade coater, a slide hopper coater, a curtain coater, a gravure coater, a flexographic gravure coater, and combinations thereof. Prior to the application of the undercoat layer, the resin surface may be subjected to a corona discharge treatment or another activation treatment such as a flame treatment. Various types of drying equipment such as hot air dryers such as linear tunnel dryers, arch dryers, air loop dryers and sine curve air float dryers, infrared dryers, heating dryers, microwave dryers, etc. Can be given. Drying conditions are arbitrary, but generally 40 ° C.
Performed at ~ 150 ° C for several seconds to 10 minutes.

The backing resin layer (B) of the support for an image material in the present invention is subjected to an activation treatment such as a corona discharge treatment or a flame treatment, and then coated with various backcoat layers to prevent static electricity or the like. Can be set up. Further, the back coat layer, JP-B-52-18020, JP-B-57-9059, JP-B-57-53940, JP-B-58-56859, JP-A-59-56859
-214849, JP-A-58-184144 and the like or inorganic antistatic agents, organic antistatic agents, hydrophilic binders, latexes, curing agents, pigments, surfactants and the like may be appropriately combined and contained. be able to.

The pulp constituting the base paper used in the practice of the present invention is described in JP-A-58-37642 and JP-A-60-679.
It is advantageous to use appropriately selected natural pulp as described or exemplified in JP-A No. 40, JP-A-60-69649, JP-A-61-35442 and the like. Natural pulp was subjected to ordinary bleaching treatment of chlorine, hypochlorite, chlorine dioxide bleaching and alkali extraction or alkali treatment and, if necessary, oxidative bleaching treatment with hydrogen peroxide, oxygen, etc., and a combination thereof. Wood pulp of softwood pulp, hardwood pulp, softwood mixed pulp is used,
Further, various kinds of recycled pulp (waste paper pulp) and the like in addition to kraft pulp, sulfite pulp, soda pulp and the like can be used.

The base paper used in the practice of the present invention may contain various additives during preparation of the stock slurry. Examples of the sizing agent include fatty acid metal salts and / or fatty acids, alkyl ketene dimer emulsions and / or epoxidized higher fatty acid amides, alkenyl or alkyl succinic anhydride emulsions and rosin derivatives described and exemplified in JP-B-62-7534. Such as dry paper strength enhancer, anionic, cationic or amphoteric polyacrylamide, polyvinyl alcohol, cationized starch, vegetable galactomannan, etc., as wet paper strength enhancer, polyamine polyamide epichlorohydrin resin, etc., as filler, clay , Kaolin, calcium carbonate, titanium oxide, etc., as a fixing agent, aluminum chloride, water-soluble aluminum salts such as bansulfate, etc., as a pH regulator, caustic soda, sodium carbonate, sulfuric acid, etc., and other JP-A-63-204251. Described in JP-A 1-266537 Exemplary coloring pigments, coloring dyes, that allowed to contain appropriately combining a fluorescent whitening agent is advantageous.

In the base paper, a composition comprising various water-soluble polymers or hydrophilic colloids or latex, an antistatic agent and additives is subjected to size press or tab size press, blade coating, air knife coating or the like. Can be contained by coating. As a water-soluble polymer or hydrophilic colloid, JP-A-1-66537
JP-A-55-4027, starch-based polymers, polyvinyl alcohol-based polymers, gelatin-based polymers, polyacrylamide-based polymers, cellulose-based polymers, etc., described in or described in JP-A-55-4027. Emulsion or latex of a copolymer containing at least ethylene and acrylic acid (or methacrylic acid) as described or exemplified in JP-A-1-80538, styrene-butadiene-based, styrene-acryl-based, vinyl acetate-acryl-based ,
Emulsion or latex of ethylene-vinyl acetate-based, butadiene-methyl methacrylate-based copolymer and their carboxy-modified copolymers, alkali metal salts such as sodium chloride and potassium chloride, calcium chloride, barium chloride, etc. as antistatic agents Alkaline earth metal salts, colloidal metal oxides such as colloidal silica, organic antistatic agents such as polystyrene sulfonate, pigments such as clay, kaolin, calcium carbonate, talc, barium sulfate, titanium oxide, etc. As a regulator, hydrochloric acid,
It is advantageous to incorporate phosphoric acid, citric acid, caustic soda and the like, and the above-mentioned additives such as coloring pigments, coloring dyes and fluorescent brighteners in an appropriate combination.

The base paper used in the practice of the present invention includes a thickness unevenness index Rpy in the papermaking direction defined below.
Is preferably 250 mV or less, more preferably 200 mV or less, and most preferably 150 mV or less.
The film thickness non-uniformity index Rpy referred to here is a value obtained by using a film thickness measuring device that moves a sample between two spherical styluses and measures a thickness variation of the sample as an electric signal through an electronic micrometer. ± 1 sensitivity range
Under the condition of 5 μm / ± 3 V, the sample was scanned at a constant speed of 1.5 m / min in the papermaking direction after the zero point adjustment to measure the thickness variation of the sample in the papermaking direction. Using an analyzer, a fast Fourier transform is performed using a Hanning window as a time window, and a power spectrum (unit: mV ² ) obtained by averaging 128 times of integration is obtained.
A value (unit: mV) obtained by summing power values in a frequency range of 25 Hz, multiplying by 2/3, and multiplying the resulting value by 1/2.
It is.

As a method of producing a base paper having a thickness unevenness index Rpy of 250 mV or less, which is preferably used in the practice of the present invention, specifically, an appropriately beaten hardwood pulp may be prepared by the following method.
0% by weight or more, preferably 50% by weight or more. Specifically, for example, as the pulp, the fiber length of the pulp after beating (JAPAN TAPPI paper pulp test method No. 5)
2-89, expressed as a length-weighted average fiber length measured in accordance with "Paper and Pulp Fiber Length Test Method"), preferably 0.45 mm to 0.62 mm, particularly preferably 0.48 mm
Hardwood kraft pulp beaten to 0.5 mm to 0.59 mm is used. The base paper is preferably formed by using a fourdrinier paper machine by using an appropriate papermaking method for the stock slurry to which the internal additive has been added so that a uniform formation can be obtained. In particular,
For example, to give an appropriate turbulence to the stock slurry, using a fourdrinier paper machine having an appropriate upper dewatering mechanism as described or exemplified in JP-A-61-284762, as a wet part press, a multi-stage press is used. Wet press,
Preferably, a wet press of three or more stages is performed, and a paper is formed so as to obtain a uniform formation by combining appropriate papermaking methods such as providing a smooth zinc roll in the final stage of the press part. , A calender using a super calender, a heat calender, or the like, to produce a base paper having a film thickness unevenness index Rpy of 250 mV or less.

The base paper mainly composed of natural pulp used in the practice of the present invention has a cutoff value of 0.8 mm measured using a stylus type three-dimensional surface roughness meter on the front side of the base paper. Center plane average roughness SRa in the papermaking direction (hereinafter referred to as center plane average roughness SRa in the papermaking direction at a cutoff value of 0.8 mm measured using a stylus type three-dimensional surface roughness meter on the front side of the base paper. The term is sometimes simply abbreviated as center plane average roughness SRa) is useful if it is 1.45 μm or less, preferably 1.40 μm or less, more preferably 1.35 μm or less, and more preferably 1.25 μm. The following are particularly preferred. The center plane average roughness SRa at a cutoff value of 0.8 mm measured using a stylus type three-dimensional surface roughness meter referred to in the present specification is:
It is defined by Expression 1.

[0034]

(Equation 1)

In Formula 1, Wx represents the length of the sample surface area in the X-axis direction (papermaking direction), Wy represents the length of the sample surface area in the Y-axis direction (direction perpendicular to the papermaking direction), and Sa Represents the area of the sample surface area.

As a method for producing a base paper having a center plane average roughness SRa of 1.45 μm or less, which is preferably used in the practice of the present invention, specifically, hardwood pulp, preferably hardwood monkey, which is easy to produce smoothness Using 15% by weight or more, preferably 30% by weight or more of pulp, multi-stage pressing is performed during the drying of the wet paper, and after the base paper is formed, at least 2% by using a machine calendar, a super calendar, a heat calendar or the like. A calendar process of a series or more, for example, a machine calendar process and / or a thermal machine calendar process was performed on a base paper as a first series of calendar processes, and then a machine calendar process was further performed as necessary as a second series and subsequent calendar processes. After performing the thermal soft calendering process described or exemplified in JP-A-4-110939, the center plane average roughness A base paper having an SRa of 1.45 μm or less can be manufactured. Further, various water-soluble polymers or hydrophilic colloids or polymer latexes are coated on a base paper or on a base paper by a size press or a tab size press, a blade coating, an air knife coating or the like to obtain a solid coating amount of 1.0 g / m ² or more, in particular allowed to contain or coating 2.2 g / m ² or more preferably.

[0037] The density of the base paper of the image material support in the present invention, preferably in the range of ^{0.90g / cm 3 ~1.15g / cm 3} , 0.95g / cm 3 ~1.15g / cm 3 more preferably in the range of the range of 1.00g / cm ³ ~1.10g / cm ³ it is particularly preferred. When the density of the base paper is less than 0.90 g / cm ³ , a support for an image material having good surface quality and excellent smoothness cannot be obtained, and when the density of the base paper is higher than 1.15 g / cm ^3, In addition, the print becomes stiff and problematic.
The thickness of the base paper used in the practice of the present invention is not particularly limited, but its basis weight is 40 g / m ^{2 to} 250 g.
/ Things m ² are useful, preferably from ^{70g / m 2 ~220g / m 2} .

Both sides of the base paper of the image material support in the present invention are covered with a resin layer containing a resin capable of forming a film. Thermoplastic resins such as polyolefin resin, polycarbonate resin, polyester resin, polyamide resin and a mixture thereof are preferable as the resin capable of forming the film. More preferred are polyethylene resins. Further, it may be covered with a resin layer composed of an electron beam curable resin described or exemplified in JP-B-60-17104.

The polyethylene resin preferably used for the surface resin layer and the back resin layer preferably used in the practice of the present invention includes a low density polyethylene resin, a medium density polyethylene resin, a high density polyethylene resin, a linear low density polyethylene resin,
Ultra-low density polyethylene resin, ethylene and propylene, copolymers of α-olefins such as butylene, ethylene and acrylic acid, acrylic acid ethyl ester, copolymers such as maleic anhydride or graft copolymers, so-called carboxy Use modified polyethylene resin, etc., polyethylene resin by high pressure radical polymerization using autoclave type reactor, tubular type reactor, etc., polyethylene resin produced by polymerization using metallocene polymerization catalyst, Ziegler method, Phillips method, etc. A polyethylene-based resin produced by polymerization using a metal catalyst other than a metallocene, and a mixture thereof, and having various densities and melt flow rates (hereinafter, a melt flow rate defined by JIS K 6760 is simply abbreviated as MFR). ), Molecular weight and molecular weight distribution can be used, , Usually with a density of 0.90
Range of 0.97g / cm ^3, MFR is 0.1 g / 10 min to 50 g / 1
Those having an MFR in the range of 0.3 g / 10 min to 40 g / 10 min for 0 minute, preferably, can be used singly or in combination.

The polyethylene resin for the back resin layer which is advantageously used in the practice of the present invention has an MFR of 10 g / 10 min.
40 g / 10 min, preferably 10 g / 10 min to 30 g / 10 min, 90 parts by weight to 65 parts by weight of a high-density polyethylene resin having a density of 0.960 g / cm ³ or more and MFR of 0.2 g / 10 minutes to 3
g / 10 minutes, preferably 0.2 g / 10 minutes to 1.5 g / 10 minutes, 10 to 35 parts by weight of a low density polyethylene resin or a medium density polyethylene resin having a density of 0.935 g / cm ³ or less. Are preferably melted and mixed in advance. As the molecular weight distribution of the low-density polyethylene resin or the medium-density polyethylene resin, those having a molecular weight of 500,000 or more are preferably 10% by weight or more, particularly preferably 12% by weight or more. If the fraction of the resin having a molecular weight of 500,000 or more is less than 10% by weight, molding processability, particularly neck-in, is undesirably increased. Here, the measurement of the molecular weight was performed using 150-C manufactured by Waters (column: GMH-XL HT manufactured by Tosoh Corporation, 8 mmφ × 30 cm × 3, solvent:
GPC method using 1,2,4-trichlorobenzene, temperature: 135 ° C., flow rate: 1 ml / min).

As the polyethylene resin for the back resin layer used in the practice of the present invention, a compound resin prepared by melting and mixing in advance is preferable. As a method for preparing a compound resin by previously melting and mixing a low-density polyethylene resin or a medium-density polyethylene resin and a high-density polyethylene resin, a simple melt mixing method, a multi-stage melt mixing method, or the like can be used. For example, using an extruder, a twin-screw extruder, a heating roll mill, a Banbury mixer, a pressure kneader, and the like, a predetermined amount of low-density or medium-density polyethylene resin and high-density polyethylene resin, and if necessary, an antioxidant A method of adding various additives such as a lubricant, melting and mixing, and then pelletizing the mixture is advantageously used.

The support for an image material according to the present invention may have a structure in which the resin in the front resin layer and the resin in the back resin layer is a thermoplastic resin, preferably a polyolefin resin, particularly preferably a polyethylene resin, on the running base paper. It is manufactured by a so-called melt extrusion coating method in which a resin composition for a front resin layer and a resin composition for a back resin layer are cast into a film from a slit die using a melt extruder and coated. Usually, using a melt extruder on a running base paper, the molten resin composition is extruded from the slit die into a film, cast and coated, and pressed between a pressure roll and a cooling roll, It is produced in a series of steps of being separated from the chill roll. At this time, the temperature of the molten film is 280
It is preferable that the temperature is in the range of ℃ to 340 ℃. As the slit die, a flat die such as a T-type die, an L-type die, or a fishtail type die is preferable, and the slit opening diameter is desirably 0.1 mm to 2 mm. Before coating the resin composition on the base paper, the base paper is preferably subjected to an activation treatment such as a corona discharge treatment or a flame treatment. Further, as described in JP-B-61-42254, a resin layer may be coated on a running base paper after spraying an ozone-containing gas onto a molten resin composition in contact with the base paper. The front and back resin layers are preferably sequentially and preferably continuously extrusion-coated on the base paper by a so-called tandem extrusion coating method. It may be coated by a multi-layer extrusion coating method, which has a multi-layer structure of more than layers. The surface resin layer surface of the image material support can be processed into a glossy surface, a finely rough surface described in JP-B-62-19732, a matte surface or a silk surface, and the back resin layer is usually matte. It is preferable to process the surface.

The thickness of the front and back resin layers of the image material support in the present invention is not particularly limited, but the thickness of the front resin layer is preferably in the range of 9 μm to 60 μm. , Preferably in the range of 12 μm to 45 μm.
The thickness of the back resin layer is usefully in the range of 5 μm to 60 μm, but is preferably in the range of 8 μm to 40 μm. Further, it is preferable that the difference in the amount of resin coating between the front and back resin layers is 3 g / m ² or more by reducing the amount of coating of the back resin layer as compared with the front resin layer.

Various additives can be contained in the front and back resin layers of the support for image materials in the present invention. JP-B 60-3430, JP-B 63-11655, JP-B1-138
No. 91, Japanese Patent Publication No. 1-38292, and titanium oxide, zinc oxide, talc and the like described or exemplified in each gazette such as JP-A-1-105245
White pigments such as calcium carbonate, fatty acid amides such as stearamide and arachidic amide, zinc stearate, calcium stearate, aluminum stearate, magnesium stearate, zinc palmitate, zinc myristate, and fatty acid metal salts such as calcium palmitate Hindered phenols described in or described in JP-A-1-105245, hindered amines, phosphorus, various antioxidants such as sulfur, cobalt blue, ultramarine, celian blue, blue pigments and dyes such as phthalocyanine blue,
Magenta pigments and dyes such as cobalt violet, fast violet and manganese violet;
Various additives such as a fluorescent whitening agent and an ultraviolet absorber described or exemplified in Japanese Patent No. 254440 can be appropriately combined and contained. These additives are preferably contained as a resin masterbatch or compound. In particular, as a method of incorporating these additives in the compound resin composition for the back resin layer used in the practice of the present invention, a high-density polyethylene resin and a low-density polyethylene resin or a medium-density polyethylene resin, Alternatively, it may be added at the time of preparing the compound resin, or a masterbatch added at a high concentration to the resin may be prepared in advance, and the masterbatch may be added to the resin at the time of melt extrusion coating.

The support for an image material in the present invention is coated with various photographic constituent layers and is used for color photographic paper, black-and-white photographic paper, typesetting photographic paper, copy photographic paper, reversal photographic material, The silver salt diffusion transfer method can be used for various purposes such as negative and positive, and printing materials. For example, a silver chloride, silver bromide, silver chlorobromide, silver iodobromide, silver chloroiodobromide emulsion layer can be provided. The silver halide photographic emulsion layer may contain a color coupler to provide a multilayer silver halide color photographic constituting layer. Further, a photographic component layer for a silver salt diffusion transfer method can be provided. As a binder for these photographic constituent layers, in addition to ordinary gelatin, hydrophilic high-molecular substances such as polyvinylpyrrolidone, polyvinyl alcohol and polysaccharide sulfate compounds can be used. Further, the above-mentioned photographic constituent layer can contain various additives. For example, as sensitizing dyes, cyanine dyes, merocyanine dyes, etc., as chemical sensitizers, water-soluble gold compounds, sulfur compounds, etc., as antifoggants or stabilizers, hydroxy-triazolopyrimidine compounds, mercapto-heterocyclic compounds, etc. , Hardening agents such as formalin, vinylsulfone compounds and aziridine compounds, coating aids such as alkylbenzenesulfonates and sulfosuccinate salts, etc., dialkylhydroquinone compounds etc. as antifouling agents, and other fluorescent brighteners, improving sharpness Dye, antistatic agent, pH adjuster,
A fogging agent and a water-soluble iridium compound, a water-soluble rhodium compound, and the like at the time of generation and dispersion of silver halide may be incorporated in an appropriate combination.

The photographic material according to the present invention is subjected to exposure, development, and stoppage in accordance with the photographic material, as described in "Photosensitive Material and Handling Method" (Kyoritsu Shuppan, Goro Miyamoto, Photographic Technology Course 2). , Fixing, bleaching, and stabilization. Further, the multi-layer silver halide color photographic material may be treated with a developer containing a development accelerator such as benzyl alcohol, thallium salt, phenidone or the like, or may be treated with a developer substantially free of benzyl alcohol. it can.

The support for an image material in the present invention can be used as a support for various thermal transfer recording image-receiving materials by coating with various thermal transfer recording image-receiving layers. Examples of the synthetic resin used for the thermal transfer recording image receiving layer include resins having an ester bond such as polyester resin, polyacrylate resin, polycarbonate resin, polyvinyl acetate resin, polyvinyl butyral resin, styrene acrylate resin, and vinyl toluene acrylate resin. , A resin having an urethane bond such as a polyurethane resin, a resin having an amide bond such as a polyamide resin, a resin having a urea bond such as a urea resin, other polycaprolactam resins, styrene resins, polyvinyl chloride resins, vinyl chloride-vinyl acetate Copolymer resins, polyacrylonitrile resins and the like can be mentioned. In addition to these resins, mixtures or copolymers thereof can also be used.

In the thermal transfer recording image-receiving layer according to the present invention,
A release agent, a pigment, and the like may be added in addition to the synthetic resin. Solid waxes such as polyethylene wax, amide wax, Teflon powder, fluorine-based,
Phosphate-based surfactants, silicone oils and the like can be mentioned. Among these release agents, silicone oil is most preferred. As the silicone oil, an oily substance can be used, but a curable type is preferred. Examples of the curable silicone oil include a reaction curable type, a photocurable type, and a catalyst curable type, and a reaction curable type silicone oil is particularly preferable. Examples of the reaction-curable silicone oil include an amino-modified silicone oil and an epoxy-modified silicone oil. The amount of the reactive silicone oil added is preferably 0.1% by weight to 20% by weight in the image receiving layer. As the pigment, extenders such as silica, calcium carbonate, titanium oxide, and zinc oxide are preferable. The thickness of the image receiving layer is preferably 0.5 μm to 20 μm, more preferably 2 μm to 10 μm.

The support for an image material in the present invention can be used as a support for various ink jet recording materials by coating various ink image receiving layers. Various binders can be contained in the ink image to improve the drying property of the ink and the sharpness of the image. Specific examples of the binder include lime-processed gelatin, acid-processed gelatin, enzyme-processed gelatin, and gelatin derivatives such as various gelatins such as phthalic acid, maleic acid, and gelatin reacted with an anhydride of dibasic acid such as fumaric acid. , Ordinary polyvinyl alcohols of various saponification degrees, carboxy-modified, cationic-modified and amphoteric polyvinyl alcohols and their derivatives, starches such as oxidized starch, cationized starch, etherified starch, and cellulose derivatives such as carboxymethylcellulose and hydroxyethylcellulose , Polyvinyl pyrrolidone, polyvinyl pyridium halide, sodium polyacrylate, methacrylic acid copolymer salt, polyethylene glycol, polypropylene glycol, polyvinyl ether, alkyl vinyl ether and maleic anhydride Polymers, styrene / maleic anhydride copolymers and salts thereof, synthetic polymers such as polyethyleneimine, styrene / butadiene copolymers, conjugated diene copolymer latexes such as methyl methacrylate / butadiene copolymer, polyvinyl acetate , Vinyl acetate
Maleic acid ester copolymer, vinyl acetate / acrylic acid ester copolymer, vinyl acetate polymer latex such as ethylene / vinyl acetate copolymer, acrylic acid ester polymer, methacrylic acid ester polymer, ethylene / acrylic acid ester Acrylic polymer or copolymer latex such as copolymer, styrene / acrylate copolymer, vinylidene chloride copolymer latex, etc., or functional group-containing monomer such as carboxyl group of these various polymers Functional group-modified polymer latex, melamine resin, aqueous adhesive such as thermosetting synthetic resin such as urea resin and polymethyl methacrylate, polyurethane resin, unsaturated polyester resin, vinyl chloride / vinyl acetate copolymer, polyvinyl butyral, Synthetic resin-based adhesive such as alkyd resin, Japanese Patent Publication 3-24906 No., JP-A-3-281383, Japanese Patent Application No. 4-2
Examples thereof include inorganic binders such as alumina sol and silica sol described and exemplified in each publication such as No. 40725, and these can be used alone or in combination.

The ink image-receiving layer of the ink-jet recording material according to the present invention may contain various additives in addition to the binder. For example, as a surfactant, an anionic surfactant such as a long-chain alkyl benzene sulfonate, a long-chain, preferably a branched alkyl sulfosuccinate, a polyalkylene oxide of a long-chain, preferably a branched alkyl group-containing phenol. Nonionic surfactants such as ethers and polyalkylene oxide ethers of long-chain alkyl alcohols, JP-B-47-9303
Silane coupling agents such as γ-aminopropyltriethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, such as fluorinated surfactants described in US Pat. No. 3,589,906 and the like; As a polymer hardener, an active halogen compound, a vinyl sulfone compound, an aziridine compound, an epoxy compound,
Acryloyl compounds, hardening agents such as isocyanate compounds, as preservatives, P-hydroxybenzoic acid ester compounds described or exemplified in JP-A-1-102551, benzisothiazolone compounds, isothiazolone compounds, and the like, JP-A-63-204251 , Described or exemplified in each publication such as JP-A 1-266537, a coloring pigment, a coloring dye, a fluorescent whitening agent,
Sodium hydroxymethanesulfonate and sodium P-toluenesulfinate as yellowing inhibitors; benzotriazole compounds having a hydroxy-di-alkylphenyl group at the 2-position as ultraviolet absorbers; Japanese Patent No. 4-1337 discloses organic or inorganic fine particles having a particle size of 0.2 μm to 5 μm, such as starch granules, barium sulfate, and silicon dioxide, as pencil writing agents such as the polyhindered phenol compounds described or exemplified in Japanese Patent No. 105245. Appropriate combinations of organopolysiloxane compounds described or exemplified in gazettes and the like, and various additives such as caustic soda, sodium carbonate, sulfuric acid, hydrochloric acid, phosphoric acid, citric acid, octyl alcohol, and silicon-based antifoaming agents as a pH adjuster Can be included.

[0051]

EXAMPLES The present invention will be described below in detail with reference to examples, but the contents of the present invention are not limited to the examples.

Examples 1 to 5 and Comparative Examples 1 and 2 Fiber length of pulp after beaten hardwood bleached kraft pulp (JAPAN TAPPI paper pulp test method No. 52-
89 After beating so that the length-weighted average fiber length measured in accordance with “Paper and pulp fiber length test method” was 0.55 mm, 100 parts by weight of pulp was mixed with cationized starch 3 Parts by weight, 0.2 parts by weight of anionic polyacrylamide, 0.4 parts by weight of an alkyl ketene dimer emulsion (as ketene dimer), 0.4 parts by weight of a polyamide epichlorohydrin resin and an appropriate amount of an optical brightener, a blue dye, A stock slurry was prepared by adding a red dye. Thereafter, the stock slurry was placed on a fourdrinier paper machine running at 200 m / min to form a web while giving appropriate turbulence, and the linear pressure was adjusted in the wet part in the range of 15 to 100 kgf / cm. After performing a three-stage wet press, the mixture is treated with a smoothing roll and then dried in a drying part for 30 to 30 minutes.
After performing a two-stage tension press in which the linear pressure was adjusted within a range of 70 kgf / cm, the resultant was dried. Thereafter, during the drying, 25 g / size press solution consisting of 4 parts by weight of carboxy-modified polyvinyl alcohol, 0.05 parts by weight of fluorescent whitening agent, 0.002 parts by weight of blue dye, 4 parts by weight of sodium chloride and 92 parts by weight of water. m ² size was pressed, the finally obtained base paper moisture is dried to be 8 wt% in absolute dry moisture, linear pressure 70
Machine calendered at kgf / cm, basis weight 170g / m ²
Having a density of 1.04 g / cm ³ , a film thickness irregularity Rpy of 20
A base paper for an image material support having 0 mV and a front-side center surface average roughness SRa of 1.15 μm was produced.

Next, the base paper surface (back surface) opposite to the side on which the image forming layer is provided is subjected to corona discharge treatment, and the following resin composition (R1) is applied to the back surface at a resin temperature of 315 ° C. and a resin thickness of 20 μm. In addition, melt extrusion coating was performed at a running speed of the base paper of 200 m / min. At this time, as a cooling roll, the center surface average roughness SRa of the back layer surface after applying the following back layer was used.
Used had a roughness of 1.15 μm. The cooling roll used was a cooling roll roughened by a liquid honing method and operated at a cooling water temperature of 12 ° C.

(Resin Composition R1) High-density polyethylene resin (density 0.967 g / cm ³ , MFR = 15 g / 10 min) 70
Parts by weight and low density polyethylene resin (density 0.924g / c
(m ³ , MFR = 0.6 g / 10 min) 30 parts by weight using a melt extruder to melt and mix in advance, and used as pellets.

Subsequently, after the surface of the base paper was subjected to a corona discharge treatment, a low-density polyethylene resin (density 0.92
0 g / cm ³ , MFR = 8.5 g / 10 min) 47.5% by weight, aluminum hydroxide (Al ₂ O _{3 with} respect to titanium dioxide)
50% by weight of anatase type titanium dioxide pigment surface-treated with 0.75% by weight) and 2.5% of zinc stearate.
20% by weight of a masterbatch of titanium dioxide pigment
Parts by weight, low density polyethylene resin (density 0.920g / c
m ³ , MFR = 4.5 g / 10 min) 65 parts by weight and high density polyethylene resin (density 0.970 g / cm ³ , MFR = 7.0 g /
10 minutes) A resin composition consisting of 15 parts by weight was heated to a resin temperature of 315
The composition was melt-extruded to a thickness of 28 μm at 200 ° C. at a running speed of the base paper of 200 m / min. In addition, the melt extrusion coating of the front and back polyethylene resins was performed by a so-called tandem method in which extrusion coating was performed sequentially. At that time, the surface of the resin layer containing the titanium dioxide pigment of the resin-coated paper was processed into a glossy surface.

Further, after the front and back resin layers are processed and wound up, the back resin layer surface of the resin-coated paper is subjected to a corona discharge treatment.
The following coating solution for the back layer was applied on-machine. As dry weight, colloidal silica: styrene latex =
The coating liquid for the back layer containing 1: 1 and further containing 0.021 g / m ² of sodium polystyrene sulfonate and another appropriate amount of a coating aid was 0.21 as a latex component (calculated as solid weight).
The coating amount was g / m ² .

After coating the back layer and before winding the resin-coated paper, the front surface of the resin surface is subjected to corona discharge treatment. After applying a predetermined DC high voltage to the application backup roll so as to obtain the value described in
g, low molecular weight gelatin (manufactured by Nitta Gelatin Co., Ltd., P-
3226) 0.3 g, 10 parts of butyl paraoxybenzoate
0.3 g of a methanol solution by weight and sulfosuccinic acid-
A subbing coating solution containing 0.45 g of a 5% by weight mixture of methanol and water of 2-ethylhexyl ester salt and adjusted to a total amount of 100 g with water is uniformly prepared so that the gelatin coating amount is 0.06 g / m ^2. Was applied on-machine to obtain a support for an image material.

Next, a blue-sensitive emulsion layer containing the following yellow-coloring coupler in order adjacent to the undercoat layer of the support for the image material:
Each coating solution for an intermediate layer containing a color-mixing inhibitor, a green-sensitive emulsion layer containing a magenta color-forming coupler, an ultraviolet-absorbing layer containing an ultraviolet-ray absorbing agent, a red-sensitive emulsion layer containing a cyan-coloring coupler, and a protective layer is coated at a speed of 220 m. A color photographic paper having a total amount of gelatin of 8 g / m ² was prepared by simultaneously coating six layers from the multilayer coating E bar at a rate of / g. As a hardening agent, 2,4-dichloro-4-hydroxy-s-triazine sodium salt (added as an aqueous solution) was used.
The silver halide color photographic paper was appropriately distributed and contained in each layer so as to be 65% by weight in consideration of the photographic characteristics, storability and the like of the silver halide color printing paper.

The blue-sensitive emulsion layer has a halogen composition of AgBr / AgCl = 95/5 produced by first aging in the presence of an appropriate amount of potassium hexachloroiridate (III), and has an optimum sensitivity of an average particle diameter of 0.8 μm. A neutral silver halide emulsion composed of a mixed crystal of [1, 0, 0] and [1, 1, 1] planes sensitized with sulfur, containing 0.6 g / m ² of silver nitrate, and 1.5 g of gelatin. / m ² and a yellow color coupler, in addition to an appropriate amount of a stabilizer, a sensitizing dye for blue sensation, a coating aid, a hardener, a thickener and the like. The intermediate layer contains, in addition to 1.4 g / m ² of gelatin, an appropriate amount of an anti-color mixing agent, a coating aid, a thickener, a hardener, and the like.
The viscosity of the coating liquid for blue-sensitive emulsion layer and the intermediate layer is adjusted to each 5.5cp and 100 cp, wet coating amount was Coating with 35 g / m ² and 7 g / m ^2, respectively.

The green-sensitive emulsion layer is composed of an appropriate amount of potassium hexachlororhodate (III) and hexachloroiridium (II).
I) AgB produced by first aging in the presence of potassium acid
An acid-processed silver halide emulsion consisting essentially of [1,0,0] planes having a halogen composition of r / AgCl = 95/5 and having an average particle diameter of 0.4 μm and sulfur-sensitized to the optimum sensitivity is reduced to 0% in terms of silver nitrate. wherein .6g / m ^2, yet another gelatin 1.2 g / m ² and the magenta color forming couplers, suitable amount of stabilizers, green sensitized light-sensitive sensitizing dyes, sharpness improving dyes, coating aids, hardening agents, thickeners And so on. The ultraviolet ray absorbing layer contains an appropriate amount of an ultraviolet ray absorbing agent, a coating aid, a thickener, a hardener and the like in addition to 1.3 g / m ² of gelatin. The viscosity of the coating liquid for green-sensitive emulsion layer and the ultraviolet absorbing layer is adjusted to each 50cp and 60 cp, wet coating amount was Coating with 18 g / m ² and 7 g / m ^2, respectively.

The red-sensitive emulsion layer contains a silver halide emulsion prepared in exactly the same manner as the green-sensitive silver halide emulsion at a silver nitrate content of 0.6 g / m ² , and further contains 1.1 g / m ^{2 of} gelatin and cyan color. In addition to the coupler, it contains an appropriate amount of a stabilizer, a sensitizing dye for redness, a sharpness improving dye, a coating aid, a hardener, a thickener, and the like. The protective layer contains an appropriate amount of a coating aid, a thickener, a hardener and the like in addition to 1.5 g / m ² of gelatin. The viscosity of the coating liquid for the protective layer Red-sensitive emulsion layer is adjusted to each 30cp and 70 cp, wet coating amount was Coating with 15 g / m ² and 10 g / m ^2, respectively.

As a method of evaluating the liquid sticking property at the beginning of coating of the coating solution for the photographic constituent layer, the distance (cm) from the starting point of coating to the achievement of coating was measured and evaluated for the sample after coating and drying. The shorter the distance, the better the liquid adhesion.

As a method for evaluating a photographic constituent layer with an emulsion film, a coated and dried sample was stored at 40 ° C. at room temperature for 5 days, exposed to a gray density of 1.5 or more, and then subjected to color development. The film sticking property was evaluated. The color of the emulsion layer was determined by scratching the emulsion surface with a nail at intervals of 1 cm vertically and horizontally after color development, making a grid-like scratch, and then rubbing the surface with a fingertip in running water. evaluated. The evaluation criteria are as follows. ：: No peeling of emulsion layer, good film formation. ：: little peeling of emulsion layer, but no problem in practical use. Δ: Peeling of the emulsion layer was slightly large, but practically the lower limit. X: The emulsion layer was peeled off a lot, but there was a problem in practical use.

Table 1 shows the obtained results.

[0065]

[Table 1]

From the results shown in Table 1, the base paper is a support for an image material in which both surfaces are coated with a resin layer, and the undercoat layer is coated on the resin layer side on which the image forming layer is provided, and The image material support (Examples 1 to 5) of the present invention in which the surface potential of the undercoat layer surface is a positive potential has a good coating property of the coating solution for the image forming layer and a good coating property of the emulsion film. It can be clearly seen that this is an excellent support for image materials. In particular, from the viewpoint of the effect of improving the adherability of the coating solution for the image forming layer, a support for an image material (Examples 2 to 5) in which the surface potential of the undercoat layer surface is at least 5 volts, preferably at least 10 Support for image material having bolts or more (Examples 4 to
5) is more preferable, and the support for the image material (Example 5) having a voltage of plus 20 volts or more is particularly preferable.

On the other hand, a support for an image material outside the present invention in which the surface potential of the undercoat layer surface is zero or minus (Comparative Examples 1 to 4)
In 2), it can be clearly understood that the coating property for the image forming layer is poor in liquid adhesion and has a problem.

Examples 6 to 11 The same as Example 2 except that the content of the sulfosuccinic acid-2-ethylhexyl ester salt used in Example 2 in the undercoat layer described in Table 2 was used. It was carried out. In addition, the surface potential of the undercoat layer surface is plus 5.
It was 0 volt.

Table 2 shows the obtained results.

[0070]

[Table 2]

Note that (Note 1) in Table 2 is as follows. (Note 1) Shows the content (mg / m ² ) of sulfasuccinic acid-2-ethylhexyl ester salt as an activator as a solid content.

From the results in Table 2, it is found that the surface potential of the undercoat layer surface is a positive potential, and the resin-coated paper-type image material support of the present invention containing an anionic surfactant in the undercoat layer (implemented) Examples 6 to 11) clearly show that the coating solution for the image forming layer is an excellent support for an image material in which the coating property for the image forming layer is good and the coating property for the emulsion film is good. In particular, from the viewpoint of the effect of improving liquid adhesion and emulsion film adhesion, the content of the anionic surfactant to be contained in the undercoat layer is as follows:
0.1 mg / m ² range is preferably ^{~3mg / m 2, 0.3mg / m} 2
More preferably in the range of ^{~2.5mg / m 2, 0.6mg / m} 2 ~
It can be seen that the range of 1.5 mg / m ² is particularly preferable.

Examples 12 to 18 In Example 2, except that the undercoat layer contained a 2% aqueous solution of chromium alum in the amount shown in Table 3 in the undercoat layer, It carried out similarly to Example 2. The surface potential of the undercoat layer was +5.0 volts.

Table 3 shows the obtained results.

[0075]

[Table 3]

(Note 2) in Table 3 is as follows. (Note 2) The content of chromium alum [potassium chromium (III) sulfate] indicates the content (mg / m ² ) as a solid content as KCr (SO ₄ ) ₂ .12H ₂ O.

From the results in Table 3, it is found that the surface potential of the undercoat layer surface is a positive potential and that the undercoat layer contains an inorganic compound containing Cr (III) ions, and is a preferred resin-coated paper type image in the present invention. The material support (Examples 13 to 18)
It can be clearly seen that the coating solution for an image forming layer is an excellent support for image materials, which has a good coating property and a good coating property with an emulsion film. In particular, in view of the effect of improving the liquid adhering property and the emulsion film adhering property, the content of the inorganic compound to be contained in the undercoat layer is calculated in the form of a hydrated salt, from 0.4 mg / m ² to 1 mg / m ^2.
Ranges preferably ^{0mg / m 2, 1.2mg / m} 2 more preferably from to 10 mg / m ^2, the range of 2mg / m ² ~10mg / m 2 is seen often particularly preferred.

Example 19 Instead of chromium alum used in Example 14, potassium alum (potassium aluminum sulfate), KAl (S
The same operation as in Example 14 was performed, except that O ₄ ) ₂ · 12H ₂ O was used, and the same results as in Example 14 were obtained.

Examples 19 to 23 Instead of the gelatin used in Example 2, lime-processed gelatin and low molecular weight gelatin (manufactured by Nitta Gelatin Co., Ltd., P-3
226) was used in combination (the total amount of gelatin used was the same as in Example 2), and the ratio was as shown in Table 4, except that it was used in the same manner as in Example 2. The surface potential of the undercoat layer was +5.0 volts.

Table 4 shows the obtained results.

[0081]

[Table 4]

From the results shown in Table 4, the resin-coated paper-type image material support of the present invention, which has a positive surface potential on the surface of the undercoat layer and contains low molecular weight gelatin in the undercoat layer (Example) Nos. 20 to 23) clearly show that the coating solution for an image forming layer is an excellent support for an image material in which the coating property is good and the coating property for an emulsion film is good. In particular, the content of the low-molecular-weight gelatin to be contained in the undercoat layer is preferably 20% by weight or more, and more preferably 40% by weight to 80% by weight, from the viewpoint of improving the liquid adhering property and the emulsion film adhering property. It can be seen that it is particularly preferable.

Examples 24 to 28 The amount of the sulfosuccinic acid-2-ethylhexyl ester salt used in Example 2 in the undercoating layer as shown in Table 5 was used. A 2% aqueous solution of chrome alum was contained in the undercoating solution in such an amount that the content in the subbing layer was as shown in Table 5, and lime-treated gelatin was replaced with lime-treated gelatin in place of the gelatin used in Example 2. Molecular weight gelatin (P-322 manufactured by Nitta Gelatin Co., Ltd.)
6) together (the total amount of gelatin used is the same as in Example 2)
However, the procedure was performed in the same manner as in Example 2 except that the ratio was set as shown in Table 5. The surface potential of the undercoat layer was +5.0 volts.

Table 5 shows the obtained results.

[0085]

[Table 5]

(Note 3) in Table 5 has the same meaning as (Note 1) in Table 2, and (Note 4) in Table 5 has the same meaning as (Note 2) in Table 3. .

From the results in Table 5, it is found that the surface potential of the undercoat layer surface is a positive potential and that the undercoat layer contains an anionic surfactant, an inorganic compound containing Cr (III) ions, and low molecular weight gelatin. Particularly preferred resin-coated paper-type image material supports in the invention (Examples 25 to 28) have particularly good wettability of the coating solution for the image forming layer and good emulsion film-attachability. It can be clearly seen that this is an excellent support for image materials.

Examples 29 to 33 In Example 2, the composition of Example 2 or Example 26 was used as the composition of the undercoat coating solution, and the surface potential of the undercoat layer after coating the undercoat layer was as shown in Table 6. Apply a predetermined DC high voltage to the application backup roll so that the value described in
The procedure was performed in the same manner as in Example 2 except that each coating solution for the multilayer silver halide color photographic component layer was coated at a coating speed of 220 m / min or 320 m / min.

Table 6 shows the obtained results.

[0090]

[Table 6]

From the results in Table 6, it is found that the surface potential of the undercoat layer surface is a positive potential, and that the undercoat layer contains an anionic surfactant, an inorganic compound containing Cr (III) ions, and low molecular weight gelatin. Particularly preferred resin-coated paper type image material supports (Examples 32 to 33) of the present invention have a particularly good coating property for the image forming layer even when the coating speed is increased, and have a coating with an emulsion film. It can be clearly seen that this is a good and particularly excellent image material support.

[0092]

According to the present invention, when the coating solution for the image forming layer is applied at a high speed, the liquid adhering property at the beginning of coating is extremely good, and sufficient adhesion between the support for the image material and the image forming layer is obtained. Paper-based resin-coated paper molds that can provide image materials and prints with good adhesion, especially in the wet and swollen state of the silver halide photographic constituent layers, and with a good coating with an emulsion film as requested. A support for an image material can be provided.

Claims (6)

[Claims] 1. A paper substrate on which one of the image forming layers is provided is coated with a resin layer (A) containing a resin (a) capable of forming a film, using a paper mainly composed of natural pulp as a substrate. In the image material support in which the paper substrate on the opposite side is coated with the resin layer (B) containing the resin (b) capable of forming a film, the resin layer (A) on the side where the image forming layer is provided
A support for an image material, characterized in that an undercoat layer is coated on one side and the surface potential of the undercoat layer surface is a positive potential. 2. The image material support according to claim 1, wherein the undercoat layer is formed by applying a corona discharge treatment to the resin layer (A) side and thereafter applying a positive potential. 3. The support according to claim 1, wherein the undercoat layer contains at least gelatin. 4. The support for an image material according to claim 1, wherein the undercoat layer contains an anionic surfactant. 5. The support according to claim 1, wherein the undercoat layer contains low molecular weight gelatin. 6. An undercoat layer comprising Cr (III) ions or Al (II)
6. The support for an image material according to claim 1, wherein the support contains an inorganic compound containing an ion.